Automated component placement apparatus

ABSTRACT

An automated component placement apparatus for use in populating circuit boards with electronic components. The apparatus includes a plurality of toolheads for picking up and placing components, a plurality of component feeders, a transport means to move PC boards between PC board assembly areas for placement of components, and a plurality of gantry systems for moving the toolheads between the component supply stations and PC board assembly areas. A plurality of programmable controllers actuates both the toolheads to grip or release components and the gantry systems to move the toolheads between the component supply stations and PC board assembly areas.

REFERENCE TO PRIOR APPLICATIONS

This application is a division of application Ser. No. 08/148,639, filedon Nov. 8, 1993, now U.S. Pat. No. 5,562,384 which is acontinuation-in-part of application Ser. No. 07/811,940, filed on Dec.23, 1991, now U.S. Pat. No. 5,259,500.

BACKGROUND OF THE INVENTION

The present invention relates generally to assembly of smallmanufactured parts. In particular, the present invention is aprogrammable, automated, gantry-mounted, apparatus for populatingcircuit boards with individual electronic components.

In the past, manufacturers employed manual labor for the assembly ofsmall parts. However, manual assembly can be slow and human error canlead to mis-assembled parts. Transportation, telecommunications,computer, consumer electronics, and other industries required productionmeans that were faster, more accurate, and more efficient. Thus,automated systems for assembling electronic circuit boards and othertypes of components have become commercially available from a number ofmanufacturers.

One such system utilizes a turret-type robot to place components from aparts feeder onto a circuit board. The turret-type robot supports atoolhead which rotates about a center axis so the work envelope of thetoolhead is limited to a circular radius. Often, circuit boards arepresented to the workstation on a linear conveyor. After a part has beenplaced, the conveyor indexes the PC board to another workstation. Also,the circuit boards are frequently presented to the toolhead just insidethe toolhead's work envelope. Thus, such workstations can only populatea single PC board per index of the supply conveyor. This may lower thespeed at which a completely populated PC board can be produced.

Moreover, since turret-type robots have a circular work envelope, it maybe difficult to place them closely adjacent to one another in a mannerthat takes up little floor space; if robots are placed too closely, thetoolheads could enter one-another's work envelope and collide. Further,such workstations commonly utilize bowl-type component feeders. Suchfeeders use a vibrating bowl to move components down a channel to apick-up station. Again, because of the bulky bowls, such feeder systemsmay be difficult to place in close proximity to each other and expensivefactory floor space can be wasted.

There is, therefore, a continuing need for improved component assemblysystems. To be commercially viable, any such system must be fast andaccurate, and efficient to manufacture. The system should also makeefficient use of space.

SUMMARY OF THE INVENTION

The present invention is an improved gantry robot, component placementapparatus for populating PC boards with electronic components in arapid, space efficient manner. In one embodiment, a plurality oftoolheads adapted to pick up and release small electronic components,pick up parts from a plurality of component feeder stations. A pluralityof gantry systems move the toolheads to an associated PC board assemblyarea. The toolheads then place the components into the appropriatelocations on PC boards located at the associated PC board assemblyareas. A transport means moves PC boards between PC board assemblyareas. The placement apparatus utilizes a plurality of programmablecontrollers to initiate the described functions.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan drawing of one multi-feeder, packaging system andcartridge support server.

FIG. 2a is a plan drawing of a component placement work station orworkcell, supported by a number of component feeders.

FIG. 2b is a plan drawing of an alternative workcell and arrangement ofthe component feeders and control arm.

FIG. 3 is an elevation drawing shown in partial cutaway of one of thecomponent feeder stations including a tool head containing gantry.

FIG. 4 is a perspective drawing of a component feeder station whereinthe tape cartridges and tool head and gantry are shown in explodedassembly.

FIG. 5 is a perspective drawing of the tape cartridge door openerassembly.

FIG. 6 is a perspective drawing shown in exploded assembly of the tapesplicing assembly and the tape splice blocks.

FIG. 7 is a perspective drawing of the connected tape ends.

FIG. 8 is a perspective drawing of the clutch driven, pinned drive tapeassembly.

FIG. 8a is a detailed cross section drawing of a portion of the drivetape in relation to a typical tape carrier.

FIG. 9 is a perspective drawing of the cover removal assembly shown inretracted relation to the tape carrier clamping assembly.

FIG. 10 is a detailed perspective drawing of the tape carrier clampingassembly.

FIG. 11 is a perspective drawing of an electronic test platform useablewith the assembly of FIG. 10.

FIG. 12 is a perspective drawing of a pneumatic/fluid test platformuseable with the assembly of FIG. 10.

FIG. 13 is a perspective drawing of the gantry and multi-facetedcomponent tool head.

FIG. 14 is a detailed perspective drawing of the multi-faceted tool headand the tool head changer.

FIG. 15a is a detailed perspective drawing of the tool head changer ofFIG. 14.

FIG. 15b is a detailed perspective drawing of a high current electricalconnector to the tool head changer.

FIG. 15c is a detailed perspective drawing of the multi-faceted toolhead.

FIG. 15d is a side elevation drawing of a four-position tool head.

FIG. 15e is a side elevation drawing of a five-position tool head.

FIG. 15f is a detailed perspective drawing shown in cutaway of theparallel gripper portion of the tool head.

FIG. 16 is a perspective drawing shown in exploded assembly drawing of acomponent tape cartridge.

FIG. 17 is a perspective drawing shown in exploded assembly of onepalletized component storage location.

FIG. 18 is a perspective drawing of a section of tape carrier includingpallets for supporting dual-in-line (DIP) components.

FIG. 19 is a perspective drawing of a section of tape carrier includingpallets having resilient component grasping projections.

FIG. 20 is a perspective drawing of a section of tape carrier includingcomponent fastener clips, with friction walled projections.

FIG. 21 is a perspective drawing of a section of a tape carrier whereinthe pallet includes projections for indexing and supporting a pluralityof populated, edge mounted, thick film hybrid components.

FIG. 22 is a perspective drawing of a section of a tape carrier whereinthe pallet includes indexed recesses for supporting edge mountedcomponents and provides spacing allowing component pickup.

FIG. 23 is a perspective drawing of a section of a tape carrier whereinthe pallet includes a multi-apertured recess for receiving surface mountcomponents.

FIG. 24 is a perspective drawing of a section of a tape carrier, similarto FIG. 23 but including lead wire spacer tabs.

FIG. 25 is a functional block diagram of the plug-mountedhydraulic/pneumatic and electrical controller.

FIGS. 26A through 26G, inclusive, show a generalized flow diagram ofcontroller operation.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1, a top plan view is shown of the organizationallayout of one possible, relatively sophisticated odd component packagingor feeder system 2. The system 2 incorporates numerous tape cartridgefeeder stations or feeders 4 of the present invention. The particulardetails of the feeder station 4 will be discussed in detail in thefollowing description.

For the system 2, a number of feeder stations 4 are positioned between atransversely mounted cartridge server conveyer 5, a cartridge loadingmeans 6 and a component conveyor 8 or assembly station (reference FIGS.2a, 2b). Depending upon the system function, whether packaging oddcomponents within the cartridges 9 or unloading odd components from thecartridges 9, the server 6 conveys cartridges 9 to and from each of theindividual feeder stations 4 in response to control signals identifyingthe filled/empty status of each of the cartridges 9.

The server 6 in response to the control signals induces a driven leadscrew assembly 10 to positionally align a cartridge carrier 12 inrelation to a particular one of the plurality of feeder stations 4. Aslide arm 14 of the carrier 12 is activated to induce an empty slidetray 16 to extend and engage one of the component cartridges 9 of theselected feeder station 4. The cartridge 9 can either be filled orempty.

Upon grasping the cartridge 9, the slide tray 16 is retracted andwithdrawn into registration with the carrier 12. Either the same or asecond slide arm 14 containing a complementary filled or empty cartridge9 is next indexed into alignment with the feeder 4 and extended to causeits cartridge to engage with the feeder 4. The parallel server conveyor5, in turn, automatically replenishes the server carrier 12 withappropriate cartridges and extracts the populated or depleted cartridges9. In a less automated setting, one or more of the foregoing functionscan be performed manually.

Mounted in transverse relation to the opposite end of each of theplurality of feeder stations 4 is a component or work object conveyer 8.If the system is populating the tape cartridges 9, each feeder 4 mayinclude a gantry mounted pick-and-place assembly 26 (reference FIG. 3)to select parts from the conveyor 8 and populate its cartridge 9.Alternatively, a plurality of assemblies, such as printed circuit boards(PCB) 7, may be conveyed in controlled relation to each feeder 4 or maybe stationed at a number of component placement stations, where thePCB's are populated with parts extracted from the tape cartridges 9 ofthe feeder stations 4.

Where the PCB's 7 are being conveyed from feeder-to-feeder, each feederstation 4 may provide a particular component type, which may be the sameor different from each neighboring station 4. Regardless, each feederstation 4 selectively extracts the components of the cartridges 9 andpositionally mounts the components to each PCB 7. Upon incrementallyadvancing each PCB 7 past the feeder stations 4, each PCB 7 can besubstantially populated with minimal human intervention.

With reference to FIG. 2a, a component placement station 19 is shownwherein nine feeder stations 4 are positioned relative to a transverseconveyer 20 including printed circuit boards 22. The PCBs 22 arepopulated via a single robotic control arm 24 having a single tool headwhich selects appropriate components from each feeder station 4 undersystem control. In contrast, the feeder stations 4 of the system 2 eachincluded a gantry arm assembly 26 containing a multi-facetedpick-and-place tool head 33, which will be described below.

In accordance with the present invention, FIG. 2b depicts an alternativecomponent placement station 19. Instead of an articulating robotic arm24, a single track mounted gantry assembly 29 is provided which containsa single multi-faceted tool head (not shown). Tool head movement isdirected above the feeders 4 and conveyor 20 within known coordinates ofa pre-defined Cartesian workcell. That is, the gantry 29 moveslongitudinally in the direction of rail 21, while the tool head extendsand retracts along the gantry and laterally of the conveyor 20. Specificgantry and tool head movement is determined for four axes of motion (X,Y, Z and theta rotate) under system control relative to the location ofthe component pallet, the PCBs 22 being populated and the availablecomponents at the feeders 4.

With attention next directed to FIGS. 3 and 4, a detailed elevation andexploded assembly drawing are shown of one of the feeder stations 4 ofFIGS. 1. For the depicted construction, a gantry arm assembly 26 isprovided at each feeder 4 which contains a multi-faceted, tool head 33.As apparent from FIGS. 2a and 2b, the structure of each feeder 4 andstation can be modified, depending upon the system requirements.

Generally, each feeder 4 is configured about a frame superstructure thatis covered with a sheet metal cabinet or housing 28. The housing 28contains the feeder control assemblies (i.e. pneumatic/hydraulic andelectric), a control panel 30 and the associated tape handlingassemblies which are described in greater detail below. The controlpanel 30 interacts with a multi-board, microprocessor based electroniccontroller 32 and associated solenoid activated, pneumatic and hydrauliccontrols, reference FIG. 25. Typically, twelve solenoids 31 are providedwith each feeder 4. A plurality of plug-in ports 38 permit couplingappropriately sized pneumatic and electrical supply sources andcommunication lines (not shown) to power the feeder 4. Mating couplersconnected to a service table (not shown) interface with the feeder atlocating pins 34 which extend from a support base 36.

FIGS. 26A through 26G disclose a functional flow diagram of theoperational source code implemented in on-board PROM memory 40.Additional instructions can be programmed by the system user via a microcomputer 42 into memory associated with the microprocessor controllerboard 44.

Mounted to a aft and operator accessible surface of the housing 28 isthe control panel 30. A plurality of manual control switches, pushbuttons, pilot lights and the like are mounted to the panel andinterface with the microprocessor board 44 via an input board. FIG. 25depicts more of the details of the manual controls. Most typically, thecontrols are accessed during initial system and feeder setup or manualoperation, such as when initially splicing the tape cartridges togetheror when performing maintenance on the feeder.

Secured to the upper and lower aft surfaces of the housing 28, justforward of the control panel 30, are dove tail slide track assemblies46, reference FIG. 4. The track assemblies 46 receive and contain thesupply and take-up component cartridges 9. Two slide assemblies 46 areprovided which are identical to one another, although only the upperassembly is depicted at FIG. 4.

Because the present feeders 4 are normally operable in a cyclic fashion,neither one of the cartridge positions continuously functions as asupply or take-up cartridge. Rather, the positions alternate relative tocomponent flow through the feeder assemblies 4. That is and as willbecome more apparent hereinafter, the tape direction alternates witheach cycle. For example and as depicted at FIG. 3, as a filled tapemoves from the upper "Supply" cartridge 9 to the lower, "Take-up"cartridge 9, during the first half of a cycle, the components areremoved.

With the emptying of the upper cartridge 9, a tape leader and connectorblock are eventually extracted and positioned for subsequent operationsto be described below. The lower cartridge 9 then contains the depletedtape and is removed. A full component cartridge 9 is then mounted to thelower cartridge position and spliced to the upper, now empty supplycartridge which becomes the take-up cartridge and the drive direction isreversed. Handling time of the populated and empty cartridges 9 is thusreduced. For certain applications, it may however be desired to providea single direction parts flow, with attendant increased cartridgehandling.

Returning attention to FIG. 1 and although the cartridges 9 can bemanually maintained, FIG. 1 depicts an automatic cartridge serverassembly 6. The server 6 includes a lead screw 10, which along with apair of slide rails 11 supports a screw follower mounted slide carrier12 and a pair of cartridge support trays 16. The server 6 may includeduplicate arrangements of upper and lower cartridge trays 16 forachieving the necessary loading/unloading at each feeder station.

Control signals, which typically are of a pulse width modulated variety,are applied from the controller 32 to drive a stepper motor 50 coupledto the lead screw 6. The slide trays 16 are thereby appropriatelyaligned with the depleted and full cartridges 9. The empty tray isextended and retracted to remove an empty cartridge 9 and the other trayre-loads the feeder 4 with a full cartridge. Tray movement is controlledto insure that the cartridges 9 are locked to the housing 28 and aforward surface adjacent a cartridge accessing station 54 (referenceFIG. 4).

Formed within the upper and lower surfaces of the housing 28, adjacentthe slide rails 46, are pairs of adjacent slots or apertures 58 andthrough which frictional drive wheels 60 extend. The drive wheels arebiased a sufficient height to extend interiorly of the cartridges 9 atmatching cartridge apertures 62 to contact and rotate the peripheralsurfaces of a tape reel 68 mounted within each cartridge 9, referenceFIG. 3. The drive wheels 60 are driven via a drive assembly 70 and reeldrive motor M2 (reference FIG. 25).

A dual drive assembly 70 is particularly provided which can beresiliently biased up or down to appropriately drive the tape of theupper or lower cartridge 9, until a sprocket tape drive assembly 72captures the tape. This occurs in a region slightly forward of thecartridges 9 and will be described in greater detail below.

Mounted forward of the reel drive assembly 70, adjacent the forward faceof each cartridge 9 are upper and lower cartridge access or tapesplicing stations 54. The splicing stations are identical to each other.Each includes a cartridge door opening assembly 76 and a splicingassembly 78. The specific constructional details of the assemblies 76and 78 can be seen upon reference to FIGS. 5 and 6.

Each door opener assembly provides a projecting lug 80 which mates withan aperture 82 formed in a spring loaded cartridge slide door 84. Thelug 80 is vertically operable via an associated solenoid and pneumaticor hydraulic directed piston 86 to raise and lower the slide door 84 inresponse to signals from the controller 32. The lower edge of the door84 is thereby released from a groove 88 formed within a surface of afemale coupler or splice block 90. The splice block 90 is attached tothe leading end of a tape leader 92 secured to the internal tape reel68. More of the details of the construction of each cartridge 9, tapeleader 92 and splice blocks 90 can be seen upon reference to FIGS. 6, 7,16 and 17.

Referring to FIG. 6 and with the release of the door 84 from the block90, the tape leader 92 is advanced to the splicing assembly 78 via athreader assembly 98. Actuation of a pair of opposed threader cylinders99 extends and retracts the splicing assembly causing it to move to andfro along paired sets of guide rods 79. A vertical control cylinder 74causes a pair of pins 94 to grasp the block 90 and contract a pair ofspring biased fingers 102. Subsequent actuation the cylinders 99 alignsand directs the tape leader 92 along lateral edge guides which rise fromthe surface of the housing 28 to loosely constrain and confine theleader travel, without allowing the leader to buckle. A male spliceblock 100 is concurrently restrained adjacent the splicing assembly 78from the previous full cartridge 9, which now comprises the take-upcartridge.

The advancement of the male connector block 90 via the cylinders 99causes the connector and splice blocks 90 and 100 to couple. That is,the fingers 102 of the male splice block 90, which include taperedfore-ends 104 and a flange 106, are inserted within the matinglongitudinal aperture 108 of the female splice block 100. With asubsequent removal of the pins 94, the fingers 102 expand to cause theflanges 106 to couple one block to the other. The splicing assembly 78is then released from the coupled blocks 90, 100.

During an uncoupling operation, the pins 94 contract the fingers 102 torelease the splice blocks from one another. The pin carriage is thenretracted to separate the blocks. During initial threading, theactuation of the cylinders 99 also advances the tape carrier 92 onto thetape drive assembly 72.

With the release of the splice blocks 90, 100, the reel drive 70 isengaged to the depleted cartridge to induce the leader 92 to be taken upinto the cartridge 9. The cartridge 9 can then be removed and replacedwith a new cartridge 9. The male splice block 100 meanwhile isrestrained at the splice station 78 and to the sprocket tape drive 72.The slide door 84 of the new cartridge is next retracted and the tapeleader 92 is advanced by the reel drive 70 to achieve coupling. As thefeeder operation cycles, the cartridge take-up and supply positionsalternate, however, the positions of the male and female splice blocksremain constant relative to the splice station 78. Once the tape endsare coupled (reference FIG. 7), the sprocket tape drive assembly 72,which is contained within the housing 28 forward of the splicingassembly 78, determines subsequent movement of the tape 110.

With reference to FIGS. 8 and 8a, the tape drive assembly generallycomprises a pair of endless, metal drive bands 112 which include aplurality of dual purpose, drive lugs 113 and drive pins 114. The pins114 mate with apertures 115 let into the lateral edges of the tape 110.The drive bands 112 are wound about and in frictional contact with threepairs of drive wheels 116, 118 and 120. The drive wheels 116 containrecesses which mate with the drive lugs 113 and are driven via a notchedbelt 122, pulley 124 and stepper motor 126. The other pairs of wheels118 and 120 act as idler wheels and are free spinning with the bands112. Slippage is thereby minimized at any of the drive wheels 116, 118or 120, which slippage could translate at the control circuitry intocomponent misalignment (either real or apparent) relative to thesplicing assembly 78, cover removal assembly 130 and lift and locateassembly 132.

In the event of a condition wherein the parts tape 110 binds or isotherwise placed under undue stress, the bands 112 can slip relative tothe tape 110 or stepper motor 126 to prevent breaking the tape carrier.The amount of slippage is dependent upon drive band tension, which isadjustable at a tensioner assembly.

Slippage induces an alarm condition and, depending upon the amount ofslippage, can be automatically corrected by the controller 32.Alternatively, should the tape 110 become disengaged from the drivebands 112, the loss of tension causes the controller 32 to stop drivepower and annunciate an appropriate operator alarm.

From the splicing assembly 78, the tape 110 is advanced past the coverremoval assembly 130 to the lift and locate station or assembly 132.With reference to FIG. 9, a detailed perspective drawing is shown of theassembly 130 which extends above the housing 28 and the path of the tapecarrier 110, forward of the splicing assembly 78. The principaloperation performed by the assembly 130 is to remove the Faraday cage orcover 134 (reference FIG. 7) from each of the plurality of storage sitesor component compartments 135 located on the tape carrier 110.

The cover removal assembly 130 includes an extractor head 140. Theextractor head 140 is capable of vertical and longitudinal movement viaa pair of fluid controlled cylinders. A cylinder 131 mounted beneath thecover 139 (reference FIG. 3) controls longitudinal movement and acylinder 143 secured to the head 140 controls vertical movement of thehead 140.

Cover removal is particularly effected upon directing each componentcompartment into alignment with the lift and locate assembly 132. Theextractor head 140 is then extended and vertically lowered withsequential control of the cylinders 131, 143 such that a number ofcontained fingers 142 are projected through mating apertures 144 of thecover 134. As the fingers 142 are lowered, they flex the cover 134 todisengage the cover from mating tabs formed into the sidewalls of araised ring that projects from the tape 110 (reference FIG. 17) torelease the cover 134 from the tape 110. Upon release, the fingers 142support the cover 134, which is then vertically retracted and cleared toone side, away from further operations. The component storagecompartment 135 is then accessed to either fill the compartment 135 orextract contained parts.

Subsequent to removing and retracting each cover 134, the edges of acomponent support pallet 146 are clamped with a pallet clamping assembly136, reference FIG. 10. The associated lift and locate assembly 132 isthen engaged to support the bottom of the pallet and test componentscontained on the pallet, if desired. FIGS. 11 and 12 depict testfixtures 137 and 138 which contain electrical and/or pneumatic and fluidconnectors which permit cursory electrical and mechanical integritytests of each component. Varieties of other fixtures can be used, whicheither attach to the assembly 132 or to the tool head 33 to test theupper surfaces of each component. Appropriate temporarycontacts/connections are thus made during testing without removing thecomponent to confirm integrity. Depending upon test results, necessaryactions can be taken to replace the defective component or pass over thecomponent.

The clamping assembly 136 includes a pair of clamps 152 which aremounted to rotate in response to the extension and retraction of a pairof cylinders 154 mounted to each side of the tape 110. As the pallet 146is clamped, the lift and locate assembly 132 is actuated to raise apallet support platform 133 (reference FIGS. 11 and 12). A number ofpins 139 project from the platform to engage apertures 156 formed in theouter periphery of the component pallet. The pallet 146 is therebysecurely constrained between the pins 139 and clamps 152. Assignificant, the pallet 146 is restrained to a known reference locationand relative to which the previously mentioned robotic arm 24 or thegantry mounted, multi-faceted tool head assembly 33 can access thecontained components. The components can also be simultaneously testedat the fixtures 137 as they are loaded or removed.

Returning attention to FIG. 3 and with additional attention to FIGS. 13and 14, general and detailed views are shown of the gantry assembly 26which supports the multi-faceted tool head assembly 33. The tool headassembly 33 contains a number of tool heads which typically containpick-and-place fingers 164. The fingers 164 are secured to a gripperassembly 165 that determines finger movement. Each gripper 165, in turn,is secured to the tool head 33 via a coupler assembly 166.

The tool head assembly 33 is supported to the gantry 26 at a pair ofdriven lead screws 168 and 170. The assembly 33 is horizontallyextensible via a servo-motor 169 and the screw 170 between eachsupported pallet 146 and the transversely mounted component containingconveyor 8 or work station 19. Otherwise, the assembly 33 is verticallyextensible via a servo-motor 173 and the screw 168.

The lead screw 170 is particularly coupled to a carrier 171 thatsupports the lead screw 168 and servo-motor 173. The servo-motor 169controls the position of the carrier 171 along the lead screw 170. Theoperation of the servo-motor 173, in turn, extends and retracts thepick-and-place fingers 164. The gripper assembly 165 causes the fingers164 to appropriately contract or expand relative to the components. Theparticular tool head brought to bear and the force applied tograsp/release each component are determined by the controller 32 viacontrol couplings to the tool head assembly 33.

A variety of tool heads, containing various facets and configurations oftools which mate with the components being accessed can be stored to oneside of the housing 28. A three position, multi-faceted tool head 180 isparticularly shown at FIG. 14. Alternatively, a single facet tool headmay be secured to the coupler assembly 166. FIGS. 15d and 15erespectively depict four and five position tool heads 181 and 182.

The detailed construction of the tool head assembly 33 is depicted inFIGS. 14, 15a-c and 15f. With attention first directed to FIG. 14, thehead assembly 33 includes a coupler assembly 166. The coupler assembly166 provides a flanged collar 174 which projects from a platform of thecarrier 171 at FIG. 13 and mates with an automatic tool coupler 176. Thecoupler 176 includes pneumatically operated fingers 177 which couple toa tool changer plate 179. A threaded collar and nut (not shown), whichis captured to the collar 174, secures the coupler 176 to the collar174.

A number of modular blocks 178 and 262, which contain pneumatic andelectrical terminations, are also detachably mounted to the coupler 176and plate 179. Appropriate conduits or wires mount between the ports ofthe blocks 178 or terminal strips of the blocks 262 to define theoperation of the tool head. The specific control signals are determinedby the microprocessor controller 44.

Flexible strip circuits may extend from the block 262 along appropriatesurfaces of the head 180 to further points of connection with otherflexible conductors that couple to the gripper 165 and tools 192. Thecircuits may comprise discrete assemblies or conductive zones or bandsformed into or on the head 180. The circuits may couple to one anotherwith a wiping action at junctions at each separately moveable assembly.

FIGS. 15a and 15b depict more of the details of the coupler assembly 176and tool plate 179. These include a pneumatic cylinder (not shown) whichextends from a linkage plate 252 that contains the fingers 177,reference FIG. 15a. The cylinder 250 actuates the fingers 177 which, inturn, couple and align with mating pins 254 in the tool plate 179. Thecoupler 176 and plate 179 are further aligned to each other at matingradial locating rings 256, 258, such as O'rings, and axial locatingslots 260 and mating pins (not shown) which extend from the coupler 176.Terminal strips on the upper and lower faces of the blocks are therebyable to engage each other.

FIG. 15b depicts an electrical connector 263 having upper and lowerterminal strips 264, 266 which couple to strips provided at the backvertical surface of each block 262. The connector 263 finds use forcoupling high current signals to the electrical termination blocks 262of the tool coupler 176 and plate 179. The block 263 exhibits a lowcoupling force and high current carrying capability via a linkage 268that actuates articulating connector arms 270, 272 to close around astationary arm 274 when the tool coupler 176 and plate 179 are coupledtogether. The arms 272 and 274 contain multiple conductive bands 276that when brought into contact with each other create a circuit havinghigh current capability.

Returning attention to the tool head assembly 180 of FIG. 14 and also toFIG. 15c, the tool head assembly 180 provides a rotationally mountedmulti-faceted, turret or gripper head 190 which supports variousdistinct grippers 165 and tools 192 at each of the facet surfaces 280.The head 190 may include any number of facets 280 and one or more of thefacets may be used for the same or different operations. As necessary,ones of the facets may also not be populated with tools.

A desired facet 280 can be rotated to position via a stepper motor 282which indexes the facets in relation to a piston or pin position lock284. The lock 284 mates with radial locating holes 286 to preciselydefine each tool position. The motor 282 couples to a geared strip orrack 288 that extends from a counterbalance plate 290. The plate 290reduces the inertia to rotate the tool facets 280 and tools, andgenerally balances the load at the head. The tool facets 280 are modularand are individually secured to the head at mounting projections 292.Associated photo optic sensors (not shown) are mounted about the head190 to monitor head movement and provide corresponding control signalsto the micro controller 42.

Particularly, secured to each facet of the head 190 is a so called"penny gripper" assembly 165. Grippers of this type find wideapplication with most components and support the pick-and-place fingers164 which are mounted to expand and contract under appropriate controlsignals to the gripper 165.

One gripper assembly 165 is depicted in detail at FIG. 15f. The gripper165 is configured about a pneumatic piston 294 which determines thegripping motion. A pin 296 extends from the piston 294 and translatesvertical piston motion to a horizontal opposing motion of the fingerbases 298 via elongated slots 300,302 let into each finger base 298. Theslots 300 are inclined at an angle less than 35 degrees from thelongitudinal axis of the piston. Two additional horizontal slots 302 andintermediate needle bearings 304 independently, horizontally direct eachfinger base 298. The finger bases 298 are preloaded under spring tensionfor accuracy with spring washers 306. The lower end of each finger base298 defines a tooling face 308 whereto the fingers 164 are attached.Sensors, such as photo optic couplers, are also mounted to the gripper165 to monitor and further control the motion of the finger bases.Electrical connections to such sensors are facilitated through theflexible circuitry and conductive bands discussed above.

Returning attention to the details of the tape 110 and cartridges 48,FIG. 16 depicts an exploded assembly drawing of a typical tape cartridge9. Each cartridge is generally comprised of an external folded shell orhousing 200. The housing 200 is typically formed of a plastic materialthat is folded to shape and appropriately secured to create a durablefive sided outer shell. The lower, open end and corner of an adjacentside receive a formed metal extrusion assembly 202 which is bonded tothe shell 200 at the edges 201, 203. The portion of the extrusion 202mounted to the short edge 203 contains the mentioned spring biased andapertured shutter door 84. The bottom surface of the extrusion 202contains a rail portion 56 which mates with the housing slide track 46.

Positioned internally of the outer shell 200 is a second folded sheetgoods liner 204 which supports a bushing or axle 206 containing endbearing surfaces and the tape reel 68. In combination, the outer shelland liners 200, 204 form a relatively rigid protective casing about thecenter mounted reel 68, tape 110 and contained components.

The tape reel 68 is formed in two halves 205, 207 and each of whichsupports a cylindrical piece 208a and 208b. The pieces 208a and 208bmate with each other to form the bushing 206. Each core portion extendsfrom the inner surface of one of the reel halves 205, 207. A pair ofscrew fasteners 209 and washers 211 mount to the bushing 206 to securethe halves 205, 207 to one another and to the liner 204 in a fashionwhich permits rotation of the reel 68 within the liner. The reel 68,otherwise, is of conventional construction.

The peripheral edges 214 of the reel 68 are widened to providefrictional drive surfaces relative to the drive wheels 60 which extendfrom the housing 28. Secured to the axle 206 is a tape leader 92 whichis formed of a length of material similar to that used to form the tapesubstrate. It is sufficiently long to permit extension to the splicestation 74 and terminates with a male splice block 90. Alternatively, afemale splice block may be secured to the leader 92.

FIG. 17 depicts an exploded perspective drawing of a single componentstorage location 135 of the component tape 110. A conventionaldual-in-line (DIP) integrated circuit 215, including opposite edgemounted parallel rows of pin connector terminals is specifically shownin relation thereto. A raised platform 230 extends from the pallet 146to elevate and support the body of the component 215 and permit room forthe gripper fingers 164 to grip the component. A complementarydepression 232 is formed in the top of the cover 134 such that thecomponent 215 is constrained between the two formed regions 230, 232 andvertical movement prevented.

The periphery of the pallet 146 and cover 134 are formed to astandardized size and shape relative to a raised annular ring 234 of thecarrier tape 110. The pallet 146 interlocks with the sidewalls 234 atfour tapered projections 236. Orthogonal flanges 158, otherwise, projectinward in the space between each tapered projection 236. A gap or space238 is provided between the bottom of the flanges 158 and the top of theprojections 236 to retain the pallet 146. Each pallet 146 is fitted intothe annular ring 234 by positioning each pallet 146 beneath the ring 234and raising the pallet. The pallet 146 flexes the projections 236 as itis raised along the sidewalls 234, and the projections 236, expandbeneath the pallet 146, which is restrained, to partially fill the uppergap 238.

Each cover 134, in turn, includes tapered projections 240 which alignwith the recess formed by each tapered sidewall projection 236. Uponlowering a cover 134 over an annular storage location 148, the coverwalls flex until the projections 240 pass the pallet 146, when the coverwalls re-expand to secure the cover 134 to the pallet 146. The cover 134is thereby constrained to the pallet 146 which, in turn, is constrainedbeneath the upper flange 158.

Cover removal is effected at each storage location 148 via the pluralityof fingers 142 which project from the cover removal assembly 130 toengage the cover in the region of the four cover recesses 240. Once thefingers 142 are lowered and engaged, the lift solenoid 138 is actuatedwhich causes the fingers 142 to remove the cover 134. The peripheraledges of the pallet 146 flex slightly to permit release, although thedimensional tolerances are typically adjusted to permit minimal flexing.Over time, it may periodically be necessary to recondition a tape 110 byreplacing worn or broken pallets 146 or covers 134. Under normalconditions and the typical flexing stresses that are encountered, it isanticipated that each tape 110 can be used in excess of twenty-fivetimes. Depending upon the quality of materials, this reusability can befurther enhanced.

In passing it is also to be appreciated that the lift and locateassembly 132 (reference FIG. 10) includes associated sensors shown atFIG. 25 which provide feedback information to the controller 30 andpick-and-place assembly 33 whereby empty storage locations 148 and/orempty component positions on a pallet 146 are detected and avoided.Extraneous equipment movement is thereby minimized.

Appreciating the varieties of odd component shapes which exist intypical PCB fabrication processes, the present tape carrier 110 isconfigured to accommodate a broad selection of component shapes andtypes. FIGS. 18 to 24 show a variety of perspective drawings of tapesegments wherein the component pallets 146 and covers 134 are variouslyformed to accommodate some of these components. FIGS. 17 and 18 show anarrangement for supporting conventional DIP packages. FIG. 19 disclosesan arrangement wherein the component pallet 146 includes resilientarcuate fingers 216 which project from the pallet surface tocompressively restrain a component, such as a crystal oscillator,between the fingers 216. FIG. 20 shows a pallet 146 including athermoformed projection 218 which is used to orient a component 220.FIG. 21 shows still another pallet 146 which includes a plurality ofspaced projections 222. Thick film hybrid assemblies 224 or the like arecontained between rows of the projections 222.

FIG. 22 shows another component pallet which also accommodates a nestededge mounting of the components. The elevated portion of the palletsurface particularly provides a plurality of cavities 226 which conformto and nest each component. A finger access channel 227 extends thewidth of the elevated platform and provides space to accommodate thegripper fingers.

FIGS. 23 and 24 disclose pallets containing flat pack receiving cavities228. Such components contain conductors on all four edges. Apertures 242are provided in each pallet to permit access by the grippers 164, tosupport the lead wire terminations and permit contact thereto fortesting. Additional apertures may be provided to support still othertest fixtures. The pallet of FIG. 24 also provides a plurality of combedprojections 232 which separate the adjacent lead wires. The combinationof the cavities 228, projections 244, and cover 134 passively restrainand fully enclose each component.

Optionally, each pallet can include a compliant corner projection 245 toseparately restrain each component to the cavity 228. When included, acover 134 is not required. In such circumstances, the fingers 164 areconstructed to expand and release the projections.

Depending upon the particular component mounting, the pick-and-placeassembly 33 or robotic arm 24 is positionally programmed relative to theprecise position of the lift and locate assembly 132 and a pallet 146and component supported thereat. The position is particularlyestablished to a tolerance of plus/minus 0.0004 inch. Such a tolerancehas heretofore not been achievable, except possibly for some largevolume, uniform component packaging systems. Such a positional accuracyand the elevated arrangement of the pallets enables the associatedhandler assemblies to not only locate singular components positioned onthe pallets, but also to select one of a number of components mounted ona pallet, such as in the constructions of FIGS. 21 and 22.

A further advantage of the present tape carrier 110 is that each feederstation 4 is essentially waste free. That is and in contrast to otherknown tape component carrier systems, a separate collection mechanismmust be provided for spent binding tape or covers. While in some casesthe binder tape may be re-utilized, this requires a re-weaving of thetape relative to the component loading operation which in turn requiresspecial equipment. The present feeder achieves both functions within asingular assembly.

While the foregoing invention has been described with respect to itspresently preferred construction, along with various consideredmodifications and improvements thereto, it is to be appreciated thatstill other modifications may suggest themselves to those of skill inthe art. Accordingly, the invention should not be narrowly interpreted.Rather, the invention should be interpreted to include all thoseequivalent embodiments within the spirit and scope of the followingclaims. Furthermore, the prior applications referenced on page 1 of thisdocument are hereby incorporated by reference in their entirety for allpurposes.

What is claimed is:
 1. An automated component placement apparatuscomprising:a plurality of toolheads adapted to pick up and releasecomponents; a plurality of component feeder stations, each adapted tocontinuously supply components to allow the toolheads to pick upcomponents for placement on PC boards; a plurality of PC board assemblyareas for releasably receiving and supporting PC boards; a transportmeans for moving the PC boards between the PC board assembly areas; aplurality of gantry systems, each gantry system including a horizontaldrive means and a generally horizontal linear track, the horizontaldrive means for supporting and driving an associated one of theplurality of toolheads in a generally horizontal direction along thegenerally horizontal linear track between at least one of the pluralityof component feeder stations and at least one of the plurality of PCboard assembly areas; and a programmable controller means coupled to theplurality of toolheads and the plurality of gantry systems and forcausing each of the plurality of toolheads to move from a position at atleast one of the plurality of component feeder stations to at least oneof the plurality of PC board assembly areas and for further causing eachof the plurality of toolheads to pick up components at at least one ofthe plurality of component feeder stations and place the components at adesired location on the PC boards.
 2. The apparatus of claim 1 whereineach of the plurality of gantry systems includes:a vertical drive meansfor driving an associated one of the plurality of toolheads in agenerally vertical direction.
 3. The apparatus of claim 1 wherein atleast one of the plurality of component feeder stations includes meansfor receiving a supply reel of tape-mounted components.
 4. The apparatusof claim 3 wherein at least one of the plurality of component feederstations includes means for receiving a supply reel of tape-mountedcomponents which is contained within a supply cartridge.
 5. Theapparatus of claim 1 wherein at least one of the plurality of componentfeeder stations includes means for releasably receiving supplycartridges of components; andthe apparatus further includes:a supplycartridge conveyor to convey supply cartridges to and from each one ofthe plurality of component feeder stations; and a supply cartridgeloading means positioned at the supply cartridge conveyor to unloadempty supply cartridges from the plurality of component feeder stationsand load full supply cartridges into the plurality of component feederstations.
 6. The apparatus of claim 3 wherein the plurality oftoolheads, the plurality of gantry systems, and the plurality ofcomponent feeder stations are positioned adjacent to one another.
 7. Theapparatus of claim 6 wherein the plurality of toolheads, the pluralityof gantry systems, and the plurality of component feeder stations aregenerally parallel to one another and a common PC board transport meanspasses generally perpendicularly across the plurality of toolheads, theplurality of gantry systems, and the plurality of component feederstations.
 8. The apparatus of claim 1 wherein at least one of theplurality of gantry systems, an associated one of the component feederstations, and an associated one of the plurality of toolheads has adedicated programmable controller means.
 9. The apparatus of claim 1 andfurther including a work station interfaced to the programmablecontroller means.